Aphasia Neuroplasticity Review

Schofield et al. (2012)

Reference

Authors	Schofield TM, Penny WD, Stephan KE, Crinion JT, Thompson AJ, Price CJ, Leff AP
Title	Changes in auditory feedback connections determine the severity of speech processing deficits after stroke
Reference	J Neurosci 2012; 32: 4260-4270
PMID	22442088
DOI	10.1523/jneurosci.4670-11.2012

Participants

Language	UK English
Inclusion criteria	Comprehension deficit
Number of individuals with aphasia	20 (plus 1 excluded: excessive head motion)
Number of control participants	26
Were any of the participants included in any previous studies?	Yes (patients recruited from database so may have participated in prior studies from this group, but not stated explicitly)
Is age reported for patients and controls, and matched?	Yes (range 35.8-90.3 years)
Is sex reported for patients and controls, and matched?	No (males: 16; females: 4; control sex not stated)
Is handedness reported for patients and controls, and matched?	No
Is time post stroke onset reported and appropriate to the study design?	Yes (mean 3.5 years, range 0.6-8.6 years)
To what extent is the nature of aphasia characterized?	Severity only
Language evaluation	CAT
Aphasia severity	11 patients (plus one excluded) had moderate comprehension impairments, 9 had severe comprehension impairments; this distribution was bimodal
Aphasia type	Not stated
First stroke only?	Yes
Stroke type	Ischemic only
To what extent is the lesion distribution characterized?	Lesion overlay
Lesion extent	Range 24.2-403.6 cc
Lesion location	L MCA
Participants notes	Demographic data includes excluded patient

Imaging

Modality	fMRI
Is the study cross-sectional or longitudinal?	Cross-sectional
If longitudinal, at what time point(s) were imaging data acquired?	—
If longitudinal, was there any intervention between the time points?	—
Is the scanner described?	Yes (Siemens Sonata 1.5 Tesla)
Is the timing of stimulus presentation and image acquisition clearly described and appropriate?	Yes
Design type	Block
Total images acquired	488
Are the imaging acquisition parameters, including coverage, adequately described and appropriate?	Yes (mostly whole brain but convexity or cerebellum excluded in some participants)
Is preprocessing and intrasubject coregistration adequately described and appropriate?	Yes
Is first level model fitting adequately described and appropriate?	Yes
Is intersubject normalization adequately described and appropriate?	Yes
Imaging notes	—

Conditions

Are the conditions clearly described?

Yes

Condition	Response type	Repetitions	All groups could do?	All individuals could do?
listening to word pairs, speaker gender judgment	Button press	18	Yes	Unknown
listening to reversed word pairs, speaker gender judgment	Button press	18	Yes	Unknown
rest	None	40 (?)	N/A	N/A

Conditions notes

—

Contrasts

Are the contrasts clearly described?

Yes

Contrast 1: listening to word pairs or reversed word pairs, speaker gender judgment vs rest

Language condition	Listening to word pairs or reversed word pairs, speaker gender judgment
Control condition	Rest
Are the conditions matched for visual demands?	No
Are the conditions matched for auditory demands?	No
Are the conditions matched for motor demands?	No
Are the conditions matched for cognitive/executive demands?	No
Is accuracy matched between the language and control tasks for all relevant groups?	N/A, tasks not comparable
Is reaction time matched between the language and control tasks for all relevant groups?	N/A, tasks not comparable
Behavioral data notes	—
Are control data reported in this paper or another that is referenced?	Yes
Does the contrast selectively activate plausible relevant language regions in the control group?	No
Are activations lateralized in the control data?	No
Control activation notes	Control data in Leff et al. (2008); auditory contrast, not intended to be language contrast
Contrast notes	—

Contrast 2: listening to word pairs, speaker gender judgment vs listening to reversed word pairs, speaker gender judgment

Language condition	Listening to word pairs, speaker gender judgment
Control condition	Listening to reversed word pairs, speaker gender judgment
Are the conditions matched for visual demands?	Yes
Are the conditions matched for auditory demands?	Yes
Are the conditions matched for motor demands?	Yes
Are the conditions matched for cognitive/executive demands?	Yes
Is accuracy matched between the language and control tasks for all relevant groups?	Unknown, not reported
Is reaction time matched between the language and control tasks for all relevant groups?	Unknown, not reported
Behavioral data notes	Behavioral data not separated by condition
Are control data reported in this paper or another that is referenced?	Yes
Does the contrast selectively activate plausible relevant language regions in the control group?	Somewhat
Are activations lateralized in the control data?	Yes
Control activation notes	Control data in Leff et al. (2008); L-lateralized activation of posterior STS
Contrast notes	—

Analyses

Are the analyses clearly described?

No** (major limitation) (see specific limitation(s) below)

Voxelwise analysis 1

First level contrast	Listening to word pairs or reversed word pairs, speaker gender judgment vs rest
Analysis class	Cross-sectional aphasia vs control
Group(s)	Moderate aphasia (n = 11) vs control
Covariate	—
Is the second level contrast valid in terms of the group(s), time point(s), and measures involved?	Yes
Is accuracy matched across the second level contrast?	Unknown, not reported
Is reaction time matched across the second level contrast?	Unknown, not reported
Behavioral data notes	—
Type of analysis	Voxelwise
Search volume	Whole brain
Correction for multiple comparisons	No correction
Software	SPM8
Voxelwise p	.001
Cluster extent	None
Statistical details	—
Findings	↓ L Heschl's gyrus
Findings notes	Structurally, HG was not significantly damaged in this group

Voxelwise analysis 2

First level contrast	Listening to word pairs or reversed word pairs, speaker gender judgment vs rest
Analysis class	Cross-sectional aphasia vs control
Group(s)	Severe aphasia (n = 9) vs control
Covariate	—
Is the second level contrast valid in terms of the group(s), time point(s), and measures involved?	Yes
Is accuracy matched across the second level contrast?	Unknown, not reported
Is reaction time matched across the second level contrast?	Unknown, not reported
Behavioral data notes	—
Type of analysis	Voxelwise
Search volume	Whole brain
Correction for multiple comparisons	Mixed** (major limitation)
Software	SPM8
Voxelwise p	MGB: SVC; elsewhere: .001
Cluster extent	None
Statistical details	—
Findings	↓ L posterior STG ↓ L Heschl's gyrus ↓ L thalamus
Findings notes	Specifically: PT, HG and MGB; structurally, the PT and HG were significantly damaged, but not the MGB

Voxelwise analysis 3

First level contrast	Listening to word pairs or reversed word pairs, speaker gender judgment vs rest
Analysis class	Cross-sectional between two groups with aphasia
Group(s)	Severe (n = 9) vs moderate (n = 11) aphasia
Covariate	—
Is the second level contrast valid in terms of the group(s), time point(s), and measures involved?	Yes
Is accuracy matched across the second level contrast?	Unknown, not reported
Is reaction time matched across the second level contrast?	Unknown, not reported
Behavioral data notes	—
Type of analysis	Voxelwise
Search volume	Whole brain
Correction for multiple comparisons	No correction
Software	SPM8
Voxelwise p	.001
Cluster extent	None
Statistical details	—
Findings	↓ L posterior STG
Findings notes	Specifically, PT; structurally, severe patients had more damage in HG and PT

Notes

Excluded analyses

Intelligibility contrasts, because findings are unclear: statements of significance in the text do not match Table 5; DCM analyses (which are the main focus of the paper)